1. Field of the Invention
The present invention relates to a lubricating oil and lubricating oil compositions for hydrogen-containing Flon (fluorohydrocarbon) refrigerants, and more particularly to a lubricating oil and lubricating oil compositions useful as lubricants for the system contacting hydrogen-containing Flon compounds, particularly for refrigerators which employ the said hydrogen-containing Flon compounds as refrigeratns.
2. Description of the Related Art
The main refrigerants employed now in refrigerator oils are Flon compounds such as trichloromonofluoromethane (Flon-11) and dichloromonofluoromethane (Flon-12) which contain no hydrogen. However, these Flon compounds are being restricted in their use internationally, since most of them reach the stratosphere without decomposing when released out into the atmosphere, and destroy the ozonosphere. Accordingly, hydrogen-containing Flon compounds, which are relatively easy to decompose, are expected to be used as refrigerants. The problem in this case is that the temperature at which the refrigerant and the lubricating oil are separated is so high that they are easily separated into two phases. Said two phase separation temperature is particularly higher in meneral oil base lubricating oil.
Alkylbenzene, which has conventionally been used as a refrigerator oil, has the disadvantages that lubricity and anti-seizure properties are insufficient, and that the oil consumption by evaporation is large.